The U.S. Presbyterian Church voted at its general assembly Thursday to allow ministers to perform same-sex weddings in states where it is legal. It also voted to change its constitution from defining marriage as being between “a man and a woman” to between “two people.” In 1991 and then in 2008, the church banned pastors from doing same-sex marriages. Both measures on Thursday passed with large majorities. The general assembly had decided in 2010 to ordain openly gay ministers. The Presbyterian Church has large liberal and conservative branches. In 2010, after that decision, many of the conservative congregations left the church. There are roughly 10,038 churches and 1.8 million members associated with the U.S. Presbyterian Church.